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Long-term occlusal changes and patient satisfaction in patients treated with and without extractions: 37 years after
Paula Cotrin1, Caroline Martins Gambardela-Tkacz1, Wilana Moura1
1Department of Orthodontics, Bauru Dental School, University of São Paulo, Bauru, São Paulo, Brazil.
Introduction:
The objective of this research was to evaluate the treatment outcomes, long-term occlusal changes, and patient satisfaction after 37 years of nonextraction and extraction treatments.
Methods:
Fifty-seven patients with Class I and Class II malocclusion were divided into 2 groups. Group 1 included 16 patients treated with nonextraction therapy, with mean initial (T1), final (T2), and long-term posttreatment (T3) ages of 13.2, 15.0, and 50.3 years, respectively. Mean treatment time (T2 - T1) and long-term follow-up time (T3 - T2) were 1.8 and 35.2 years, respectively. Group 2 included 41 patients treated with extraction of 4 first premolars, with mean ages at T1, T2, and T3 of 13.3, 15.6, and 53.6 years, respectively. Mean treatment (T2 - T1) and long-term follow-up (T3 - T2) times were 2.3 and 37.9 years, respectively. The Peer Assessment Rating (PAR) index and Objective Grading System (OGS) indexes were evaluated at T1, T2, and T3 stages. The subjects also answered an online questionnaire regarding esthetic and occlusal self-perception at T3. Intergroup comparison was performed with t tests.
Results:
The PAR index improved with treatment and similarly worsened at T3 for both groups. OGS scores were close to the passing score at T2 for both groups. The nonextraction group presented worse OGS scores at T3 than the extraction group. Nonextraction patients perceived more changes in alignment over time, but overall satisfaction was similar.
Conclusions:
The PAR index improved with treatment, and the PAR and OGS scores showed a significant increase, indicating great occlusal changes in the long-term stage. The nonextraction group showed more occlusal changes and perceived more changes in their alignment over time, but overall patient satisfaction was similar in both groups.
